Geochronology and evolution of a complex barrier, Younghusband Peninsula, South Australia

Dillenburg, Sérgio Rebello; Hesp, Patrick A.; Keane, Robert E.; Silva, Graziela Miot da; Sawakuchi, André Oliveira; Moffat, Ian; Barboza, Eduardo Guimarães; Bitencourt, Volney Junior Borges de

doi:10.1016/j.geomorph.2020.107044

Cited by 22 publications

(11 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This vertical distance is also found 50 km to the north of the Curumim barrier [8]. In contrast, on coasts such as Troia Peninsula (Portugal) (macro-tidal range) and at The Granites (South Australia) (moderate wave energy but macro-tidal range), this vertical distance is around 4.6 and 3.0 m, respectively [13,52]. Thus, it is clear the great influence of the tidal range on the altitude of the contact between foredune and backshore deposits.…”

Section: Resultsmentioning

confidence: 69%

Holocene Sea-Level Changes in Southern Brazil Based on High-Resolution Radar Stratigraphy

et al. 2021

View full text Add to dashboard Cite

This paper focuses on high-resolution coastal stratigraphy data, which were revealed by the Ground Penetrating Radar (GPR) system. Surveys performed with GPR on the surface of prograded barriers reveal patterns of reflections that allow the interpretation of the geometry and stratigraphy of coastal deposits in a continuous mode. At the Curumim prograded barrier in southern Brazil (29°30′ S–49°53′ W), a two-dimensional transverse GPR survey revealed, with high precision, a serial of contacts between aeolian deposits of relict foredunes and relict beach deposits that have a strong correlation with sea level. In a 4 km GPR profile, a total of 24 of these contacts were identified. The high accurate spatial positioning of the contacts combined with Optical Stimulated Luminescence dating resulted in the first confident sea-level curve that tells the history of sea-level changes during the last 7 ka on the southernmost sector of the Brazilian coast. The curve shows that sea-level was still rising before 6 ka BP, with a maximum level of 1.9 m reached close to 5 ka BP; after that, sea-level started to falling slowly until around 4 ka BP when fall accelerated.

show abstract

Section: Resultsmentioning

confidence: 69%

Holocene Sea-Level Changes in Southern Brazil Based on High-Resolution Radar Stratigraphy

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Indeed, drowned and cemented wave-and wind-built beach ridges can form linear ridges composed of beachrocks and aeolianites reaching heights >30 m (Salzmann et al, 2013) and lengths >1000 km (Lebrec et al, 2021(Lebrec et al, , 2022a. Those non-bioconstructed ridges can form barriers several 100's km long (Dillenburg et al, 2020), and protect lagoons, hence exhibiting morphologies similar to drowned barrier reefs (Salzmann et al, 2013;Figure 9). In addition, it is well documented from outcrop studies that coastal deposits, and in particular aeolianites, can be stacked on top of each other and reach significant thicknesses (Figure 9; Carew & Mylroie, 2001).…”

Section: F I G U R Ementioning

confidence: 99%

Differentiating reefal ridges from relict coastal ridges: Lessons from the seismic geomorphologic study of buried Miocene buildups (North West Shelf, Australia)

et al. 2023

View full text Add to dashboard Cite

Linear buildups formed in tropical carbonate environments are often interpreted as bioconstructed reefs. Nevertheless, coastal processes can also form extensive sedimentary ridges exhibiting buildup morphologies. This study investigates two Miocene ridges developed along the Australian North West Shelf using 3D seismic and well data. Ridge 1 is ca. 30 m thick and >60 km long, and it is made of foraminiferal pack‐grainstones. It protects a lagoon with pinnacle morphologies. Ridge 2 is ca. 150 m thick and >80 km long. It is composed of quartz sand forming lobes. Both ridges have a continuous curvilinear front and are in a mid‐shelf setting. They mimic the modern Australian coastline. It is then proposed that Ridge 1 is either: (1) a barrier reef developed on a drowned shoreline, or (2) stacked carbonate aeolianites and beachrocks acting as a barrier. Ridge 2 is interpreted as stacked deltaic sands. This study demonstrates that lithified and buried coastal features of carbonate and siliciclastic nature can form extensive ridges exhibiting buildup morphologies. It is proposed that ridges formed by stacked coastal features are overall continuous with a curvilinear front, while reefal ridges are more discontinuous and exhibit deeper and more stable passes.

show abstract

“…Starting in the late 1950s and 1960s were discussions on the genesis of beach ridges (see Oliver et al (2017c) for review) which progressed to coastal barrier stratigraphy and chronology (Roy and Thom, 1981;Roy et al, 1980;Thom (1965), Thom (1978Thom ( , 1984; Thom et al, 1981aThom et al, , 1981bThom et al, , 1981c. A resurgence of coastal barrier studies in Australia, and especially utilising coastal barriers as archives of palaeoenvironmental data in the last 20 years, has been supported by advances in chronology such as Optically Stimulated Luminescence (OSL) dating and geophysics such as Ground Penetrating Radar (GPR) (Brooke et al, 2008a(Brooke et al, , 2008b(Brooke et al, , 2019Dillenburg et al, 2020;Forsyth et al, 2010Forsyth et al, , 2012Kennedy et al, 2020;Murray-Wallace et al 2002;Nott et al (2009Nott et al ( , 2015; Oliver et al (2017aOliver et al ( , 2018Oliver et al ( , 2020aOliver et al ( , 2022; Tamura et al, 2018Tamura et al, , 2019. Coastal barrier research New South Wales (NSW) coast in recent years has focused on revising the depositional history of prograded barriers and understanding sediment sources for barrier deposition (Carvalho et al, 2019;Goodwin et al, 2006;McBride et al, 2021;Oliver and Woodroffe, 2016;Oliver et al, 2015Oliver et al, , 2017bOliver et al, , 2019Oliver et al, , 2020b.…”

Section: Introductionmentioning

confidence: 99%

Holocene estuary infill leads to coastal barrier initiation from fluvial sand supply in southeastern Australia

Oliver,

Owers,

Tamura

et al. 2023

The Holocene

View full text Add to dashboard Cite

A morphodynamic approach to coastal evolution involves recognition of internal thresholds, feedbacks and boundary conditions and should underpin coastal management. The Holocene evolution of the Bega River estuary and Tathra Beach coastal barrier was examined integrating existing sediment cores and radiocarbon dating, airborne terrestrial and marine Lidar and OSL dating. Sediment coring reveals the Bega River estuary began infilling with fluvial sand once sea levels stabilised at or near their present elevation. Radiocarbon dating suggests a prograding fluvial delta reached the coast approximately 4000–2250 years BP. Barrier deposition commenced ~3200 years ago coinciding with the arrival of fluvial sand at the coast. Shoreline progradation of the Tathra barrier occurred at 0.15 m/year from ~3200 years to present forming a sequence of ~17 foredune ridges which were each active for an average of ~190 years. In the past ~500 years, a sand spit has restricted the entrance of the Bega River estuary to the northern end of the embayment. The infill of the Bega River estuary over the Holocene represents an internal morphodynamic threshold or tipping point, which then enabled coastal barrier deposition as fluvial sand reached the coast. The coastal system approaches another threshold as the Tathra embayment infills, and sediment may be transported northward out of the embayment. At Tathra Beach, the positive sediment budget which resulted in barrier progradation is approximately 0.55 m3/m/year. This signal is masked on the yearly to decadal scale by fluctuations in beach volume an order of magnitude greater (5–20 m3/m/year depending on the timeframe examined). Thus longer-term datasets of beach change or reconstructions from the geological record are needed to underpin management decisions which will impact shorelines decades or centuries into the future.

show abstract

Geochronology and evolution of a complex barrier, Younghusband Peninsula, South Australia

Cited by 22 publications

References 57 publications

Holocene Sea-Level Changes in Southern Brazil Based on High-Resolution Radar Stratigraphy

Holocene Sea-Level Changes in Southern Brazil Based on High-Resolution Radar Stratigraphy

Differentiating reefal ridges from relict coastal ridges: Lessons from the seismic geomorphologic study of buried Miocene buildups (North West Shelf, Australia)

Holocene estuary infill leads to coastal barrier initiation from fluvial sand supply in southeastern Australia

Contact Info

Product

Resources

About